I finally got this new to me dragster running. But havnt found out the correct setting to idle on the primer plus. I changed out the faucet pump for a holley 25 gph pump. I know this is vague but can anyone tell me what needle valve setting they are using to be able to idle to lanes and back down return road. Thanks for your time. Also alchol carb is idleing at 1300 when running but was cold idle as I unloaded it at track and got a free car wash from the rain. So no racing.

Does this have a nitrous type plate between the carb and intake manifold that the gasoline is plumbed to?

No it has the plate that comes with the primer plus and it is spraying up like it is suppose to. Thanks for the reply

I gave up years ago trying to get mine to idle using the primer plus. I use it to start only on gas, and then switch to meth as soon as it fires, all idling to the staging lanes is done with the lean-out valve set to build heat. On the return road I use the fan and water pump to cool down. My system is older, and uses removable jets, not equipped with the needle valve like the newer systems.

Jeff, seems to me with a carb you would be still be pulling fuel from the carb making it dead fat. With injection the fuel is shut off, how are you shutting off the fuel to the carb and or preventing the fuel in the bowls from being pulled into the engine, even if you shut off the pump the bowls would still empty into the engine

Thanks top fuel. Looks to me it might be a little difficult and require some luck to get it right. I havnt messed with it much. Thought I would ask here to get a jump on it as this is all new to me. Thanks again.

Steve yes that's true it would probably suck bowls dry. I tried to get it set before I ever put alcohol in it with no luck. But I was impatient. Worked hard getting things done to go racing but when I got there it rained like crazy and when I returned to the farm it was bone dry. I think I must have bad neighbors because the rain keeps missing me. Surely it can't be me. I was hoping someone was having luck making this work and could give me a dial setting to get me close. But if not it is nice to be able to prime it to start easier. I have a slide lean out valve so I can use that. Just trying to save on alcohol so I don't have to carry so much to the races. Thanks for your reply.

I would try to be as methodical about it as you can. I assume you have an electric pump for the carb.
Start it up as usual. Take a stab at the needle setting even if it is fat. Turn off the carb pump. As it starts to empty the bowls you will hear the idle come up. Turn on the primer plus. Lean it down until it isn't fat on the primer. Dry idle in gear to make sure it isn't too lean to idle under a little load. Finished.
Shouldn't that work?

I have limited experience with the needle valve primer plus, yet my first impression is good. Of course, each engine will respond differently, be patent and make small changes. It takes some experimenting, it is important to make small changes [maybe 1/8th turn] because you can go past the sweet spot.

At this time, I find Ron's injection with primer plus to be a good setup. It takes some "piddling/tweaking" in small steps but it will operate as expected.

Reach out to Scott Offerman or James on the Killer Ron's site. The carb with primer plus may take some special details.

My primer + uses a holley blue and regulator with the adjustable needle valve under a toilet. The orfice opening to the spray bar has a .051 nozzle jet in it.

When I purchased my car it had this system installed but it would never idle properly no matter how the needle valve was adjusted.

I had the primer plate off when the engine was being serviced and was looking at it and noticed that whatever sealer that was used to seal the inlet fitting to the spray bar was broken away.

I removed the inlet fitting and the bar stayed in place being held by the plug in the other end of the plate. I called Rons and told them what I did, and they said if the spray bar was properly sealed to the inlet fitting I would have twisted the spray bar damaging it when removing the fitting. They said to use JB weld to seal the spray bar to the fitting which I did.

When my engine was put back in I set the needle valve to 1/4 turn and it actually idled properly for the first time. I believe it is now set just short of 1/4 turn and works as advertised.

Jeff,

First of all you should be headed to Denver to go race with us. I know, you think you need to earn a living or some such. Anyway, here is my take on the Primer Plus.

I have run it both with a Carburetor and a Terminator. The fuel injection works much better since you can shut off the injector pretty much instantly and the car will just idle on gas.

Carb is frankly a pain in the a-z-z with the primer but it will work. Are you running a mechanical pump with the alky or electric? I think you told me electric but I'm old and forget s--t easily.

Throw the needle valve in the trash, you don't need it in my opinion. Mine ended up screwing up anyway so I just chunked it. Your engine is bigger than mine so for Amarillo start out with about a .036 pill for the primer. About a .040 pill for Dallas and about a .032 for Denver.

Make sure the bowls are empty before you start it up. Obviously make sure the alky pump is NOT running or else use the fuel shutoff if you have a belt pump. Also you MUST have some type of solenoid after the electric pump. If not it will be running on both fuels. Been there, done that!

One other thing, I'm assuming you have an open spacer under the carb so the primer plus has some room to spray. I don't like having it right under the carb even though it might work.

Use decent fuel, even at our high altitude. I used AV-Gas. It works great. You might sneak by with premium but I would not.

Now that you have the car idling correctly with no alky in the mix you can then switch over to alky and turn off the primer plus.

Now comes the problem with the primer and carburetor. You are idling on gas and the bowls are DRY. You flip the switch to fill the bowls and your back accelerator pump is probably empty.

This happens especially if you changed jets. You MUST work the pump in order to fill it or you will pull to the line and not get a full pump shot.

With injection, no worries. That's about all I have, sorry it was so long winded. If you have any questions call me this afternoon. I'm making Jimmy drive so I'll be able to visit. Gotta go get packed, we're leaving at noon.

Good luck!

quote:

Originally posted by Cashflow:

Throw the needle valve in the trash, you don't need it in my opinion. Mine ended up screwing up anyway so I just chunked it. Your engine is bigger than mine so for Amarillo start out with about a .036 pill for the primer. About a .040 pill for Dallas and about a .032 for Denver.

That's a really helpful post Vern, this is the only part that I do differently. I use the needle valve daily on my wife's car. When we first start it I open the valve a turn to richen the primer for cold start. Once its running and starting to build some heat I'll close it back up. I always run the primer about as lean as I can get it since I've fouled plugs on gas before, costing me a round, so I'm always careful about that. I know that there are different needle valves but I do like the one that comes with the primer plus nowadays. I had an old needle valve that was so sensitive it was hard to get the proper adjustment. I think using the needle valve instead of changing pills in the primer allows for more adjustability to current weather conditions and engine fuel requirements.

I do the same thing in my car (richen the mixture for cold start, then lean it out as the engine warms) using my pulse width modulator with high pressure injector that I can adjust with a knob on my dash.

As far as primer fuel we've had good luck with premium ethanol free unleaded. The engine will tell you what it needs - if the primer fuel doesn't have enough octane the engine will "run on" after you shut it off on the primer.

Jamie